The pediatric-to-adult care transition has been correlated with worse outcomes, including increased mortality. Emerging adults transitioning from child-specific healthcare facilities to adult hospitals encounter marked differences in environment, culture, and processes of care. Accordingly, emerging adults may experience care differently than other hospitalized adults. We performed a retrospective cohort study of patients admitted to a large urban safety net hospital and compared all domains of patient experience between patients in 3 cohorts: ages 18 to 21, 22 to 25, and 26 years and older. We found that patient experience for emerging adults aged 18 to 21, and, to a lesser extent, aged 22 to 25, was significantly and substantially worse as compared to adults aged 26 and older. The domains of worsened experience were widespread and profound, with a 38-percentile difference in overall experience between emerging adults and established adults. While emerging adults experienced care worse in nearly all domains measured, the greatest differences were found in those pertinent to relationships between patients and care providers, suggesting a substantial deficit in our understanding of the preferences and values of emerging adults.